MCQ
A current carrying infinitely long wire is kept along the diameter of a circular wire loop, without touching it. The correct statement $(s)$ is (are) :

$(A)$ the emf induced in the loop is zero if the current is constant.

$(B)$ The emf induced in the loop is finite if the current is constant.

$(C)$ The emf induced in the loop is zero if the current decreases at a steady rate.

$(D)$ Theemf induced in the loop is finite if the current decreases at a steady rate.

  • $(A,C)$
  • B
    $(B,D)$
  • C
    $(B,C)$
  • D
    $(A,D)$

Answer

Correct option: A.
$(A,C)$
a
$(\phi)_{\text {luep }}=0$ for all cases

so induced emf $=0$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Three identical capacitors are given a charge $Q$ each and they are then allowed to discharge through resistance $R_1, R_2\,$ and $\,R_3$. Their charges, as a function of time shown in the graph below. The smallest of the three resistance is
The linear portions of the characteristic curves of a triode valve give the following readings The plate resistance is.......$ohms$

${{V}_{g}}$(volt)

$0$

$- 2$

$- 4$

$- 6$

${{I}_{p}}(mA)$ for ${{V}_{p}}=150volts$

$ 15$

$12.5$

$10$

$7.5$

${{I}_{p}}(mA)$ for ${{V}_{p}}=120volts$

$10$

$7.5$

$5$

$2.5$

$AC$ voltage $V(t)=20\,sin\omega \,t$ of frequency $50\, {Hz}$ is applied to a parallel plate capacitor. The separation between the plates is $2\, {mm}$ and the area is $1 \,{m}^{2}$. The amplitude of the oscillating displacement current for the applied $AC$ voltage is ...... $\mu {A}$.

[Take $\left.\varepsilon_{0}=8.85 \times 10^{-12} \,{F} / {m}\right]$

To get line spectrum, the substances are excited in their:
The error in measuring the current with a tangent galvanometer is minimum when the deflection is about
Which of the following parameters is the same for molecules of all gases at a given temperature?
A long solenoid of length L has a mean diameter D. It has n layers of windings of N turns each. If it carries a current ‘i’ the magnetic field at its centre will be
The work function of three metals $A , B$ and C are $1.92 eV , 2 eV , 5 eV$ respectively. On the basis of Einstein equation, when radiation of wavelength 4100 Å is used, the emission of electrons will be :
A metal target with atomic number $Z=46$ is bombarded with a high energy electron beam. The emission of $X$-rays from the target is analyzed. The ratio $r$ of the wavelengths of the $K_\alpha$-line and the cut-off is found to be $r=2$. If the same electron beam bombards another metal target with $Z=41$, the value of $r$ will be
A voltmeter having a resistance of $998\, ohms$ is connected to a cell of $e.m.f.$ $2\, volt$ and internal resistance $2\, ohm$. The error in the measurement of $e.m.f.$ will be